Imaging modalities for renal artery stenosis in suspected renovascular hypertension: prospective intraindividual comparison of color Doppler US, CT angiography, GD-enhanced MR angiography, and digital substraction angiography

The aim of the study was to evaluate the diagnostic accuracy of Color Doppler US, CT Angiography (CTA), and GD-enhanced MR Angiography (MRA) compared with digital subtraction angiography (DSA) for the detection of renal artery stenosis in patients with clinically suspected renovascular hypertension. Fifty-eight patients with suspected renovascular hypertension were enrolled in the study. All patients underwent Color Doppler US, CTA and GD-enhanced MRA. DSA was the gold standard method for the number of renal arteries, existence and degree of stenosis, or evidence of fibromuscular dysplasia. DSA depicted 132 renal arteries, 16 stenoses, and 4 arteries with fibromuscular dysplasia. Color Doppler US failed to detect 1 main and 14 polar arteries. CTA depicted all main renal arteries and 7/16 polar arteries, but failed to detect stenosis in two accessory vessels. Likewise, MRA did not detect stenotic accessory renal arteries, depicted 9/16 polar renal arteries, but missed two main renal arteries. All methods depicted the four main renal arteries with fibromuscular dysplasia. The overall sensitivity, specificity, and positive and negative predictive accuracy were 75%, 89.6%, 60% and 94.6%, respectively, for color Doppler US; 94%, 93%, 71%, and 99%, respectively, for CTA; and 90%, 94.1%, 75%, and 98%, respectively, for GD-enhanced MRA. CTA and GD-enhanced MRA have comparable and satisfactory results with respect to the negative predictive accuracy of the suspected renal artery stenosis. The concept of an imaging algorithm including US as screening test when appropriate and CTA or MRA as the second step-procedure is suggested. Therefore, DSA may be reserved for cases with major discrepancies or therapeutic interventions.     

Imaging Modalities for Renal Artery Stenosis in Suspected Renovascular Hypertension: Prospective Intraindividual Comparison of Color Doppler US,CT Angiography,GD-Enhanced MR Angiography,and Digital Substraction Angiography

The aim of the study was to evaluate the diagnostic accuracy of Color Doppler US, CT Angiography (CTA), and GD-enhanced MR Angiography (MRA) compared with digital subtraction angiography (DSA) for the detection of renal artery stenosis in patients with clinically suspected renovascular hypertension. Fifty-eight patients with suspected renovascular hypertension were enrolled in the study. All patients underwent Color Doppler US, CTA and GD-enhanced MRA. DSA was the gold standard method for the number of renal arteries, existence and degree of stenosis, or evidence of fibromuscular dysplasia. DSA depicted 132 renal arteries, 16 stenoses, and 4 arteries with fibromuscular dysplasia. Color Doppler US failed to detect 1 main and 14 polar arteries. CTA depicted all main renal arteries and 7/16 polar arteries, but failed to detect stenosis in two accessory vessels. Likewise, MRA did not detect stenotic accessory renal arteries, depicted 9/16 polar renal arteries, but missed two main renal arteries. All methods depicted the four main renal arteries with fibromuscular dysplasia. The overall sensitivity, specificity, and positive and negative predictive accuracy were 75%, 89.6%, 60% and 94.6%, respectively, for color Doppler US; 94%, 93%, 71%, and 99%, respectively, for CTA; and 90%, 94.1%, 75%, and 98%, respectively, for GD-enhanced MRA. CTA and GD-enhanced MRA have comparable and satisfactory results with respect to the negative predictive accuracy of the suspected renal artery stenosis. The concept of an imaging algorithm including US as screening test when appropriate and CTA or MRA as the second step-procedure is suggested. Therefore, DSA may be reserved for cases with major discrepancies or therapeutic interventions.     

Fibromuscular dysplasia of the renal arteries: a radiological review

Fibromuscular dysplasia is the most common cause of renovascular hypertension in young patients. Digital subtraction angiography is still the best investigation used to determine the location, extent and complication of renal artery involvement. String of beads appearance (reflecting multiple stenoses), aneurysms, focal or tubular stenosis are classic angiographic appearances. The aim of this pictorial essay is to illustrate the various imaging findings of renal artery fibromuscular dysplasia.     

An unusual case of fibromuscular dysplasia

The case of a patient with abdominal angina due to fibromuscular dysplasia is described. Arteriography revealed dysplasia of both renal arteries and occlusion at their origins of both coeliac and mesenteric arteries. Digital subtraction angiography later showed fibromuscular dysplasia of both carotid artery systems. An unusually long right internal iliac artery allowed it to be anastomosed to the superior mesenteric artery. Follow-up studies have confirmed patency of this reconstruction.     

Fibromuscular dysplasia associated with simultaneous spontaneous dissection of four peripheral arteries in a 30-year-old man

A 30-year-old man had a sudden bout of severe abdominal pain. An enhanced computed tomographic scan revealed dissections of the celiac artery, superior mesenteric artery, left renal artery, and right external iliac artery; stenosis of the right renal artery; and left kidney infarction. After careful evaluation, the patient was diagnosed with fibromuscular dysplasia (medial dysplasia), based on the findings obtained from the enhanced computed tomographic scan. This case is extremely rare because fibromuscular dysplasia occurred concurrently with simultaneous spontaneous dissections of four peripheral arteries in a young man.     

Rapid Progression of Native Renal Artery Fibromuscular Dysplasia Following Kidney Donation

Fibromuscular dysplasia is the second commonest anatomical abnormality apart from multiple renal arteries in the potential live donors. Pretransplant evaluation of the donors may include an angiography to evaluate the renal arteries, and failure to recognize renal arterial stenosis, particularly fibromuscular dysplasia, by noninvasive methods may eventually lead to hypertension and ischemic renal failure. We report a case of fibromuscular dysplasia that was undetected by computed tomographic angiography prior to donation. One year after kidney donation, it rapidly progressed to severe symptomatic stenosis with hypertension and acute renal failure. Following renal artery angioplasty, her blood pressure normalized over a period of 2 weeks without any need for antihypertensive medications and the serum creatinine returned to her baseline. The acceptability of renal donors with fibromuscular dysplasia depends on the age, race and the availability of the other suitable donors. Mild fibromuscular dysplasia in a normotensive potential renal donor cannot be considered a benign condition. Such donors need regular follow-up postdonation for timely detection and treatment.     

Isolated thigh claudication as a result of fibromuscular dysplasia of the deep femoral artery.

Isolated thigh claudication as a result of fibromuscular dysplasia of the deep femoral artery has not previously been reported. This case report describes a patient with fibromuscular dysplasia of the carotid arteries in whom progressive unilateral thigh claudication developed despite normal femoral pulses. Deep femoral artery occlusion caused by fibromuscular dysplasia was successfully treated by common femoral to distal deep femoral artery bypass. Fibromuscular dysplasia of the infrainguinal arteries is rare but should be included as a possible cause of lower extremity ischemic symptoms.     

Renal fibromuscular dysplasia

Renal artery fibromuscular dysplasia is a noninflammatory, nonatherosclerotic vasculopathy that can affect renal arteries at various degrees with different severity. The etiology is still unknown, but there is a strong belief that a genetic disorder is the main cause for the pathogenesis of this disease. The main presentation is a sudden onset of recalcitrant hypertension at a young age, which is usually resistant to medical treatment. Once renal artery fibromuscular dysplasia is suspected, several diagnostic tools are available to make an accurate diagnosis. The advent of minimally invasive interventions has revolutionized the options for treatment. This update should provide the clinician with a base understanding of available evidence for diagnosing and treating renal artery fibromuscular dysplasia.     

Multivisceral Fibromuscular Dysplasia in Childhood: Case Report and Review of the Literature

We report here a 9-year-old girl with fibromuscular dysplasia of many muscular arteries including both renal and internal carotid arteries, the celiac artery, superior mesenteric artery, and one external carotid artery. She suffered from severe renovascular hypertension with beginning secondary cardiac decompensation, typical angina abdominalis, and neurological signs, including severe headaches and hemianopsia. Surgery was performed for all major vessels and the outcome is good 2.5 years after the operation. The clinical presentation, differential diagnosis, and treatment options of fibromuscular dysplasia in childhood are discussed and the literature is reviewed.     

Diagnosis, management, and future developments of fibromuscular dysplasia

Fibromuscular dysplasia (FMD) is a nonatherosclerotic noninflammatory vascular disease that primarily affects women from age 20 to 60, but may also occur in infants and children, men, and the elderly. It most commonly affects the renal and carotid arteries but has been observed in almost every artery in the body. FMD has been considered rare and thus is often underdiagnosed and poorly understood by many health care providers. There are, however, data to suggest that FMD is much more common than previously thought, perhaps affecting as many as 4% of adult women. When it affects the renal arteries, the most common presentation is hypertension. When it affects the carotid or vertebral arteries, the patient may present with transient ischemic attack or stroke, or dissection. An increasing number of patients are asymptomatic and are only discovered incidentally when imaging is performed for some other reason or by the detection of an asymptomatic bruit. FMD should be considered in the differential diagnosis of a young person with a cervical bruit; a "swishing" sound in the ear(s); transient ischemic attack, stroke, or dissection of an artery; or in individuals aged ≤ 35 years with onset hypertension. Treatment consists of antiplatelet therapy for asymptomatic individuals and percutaneous balloon angioplasty for patients with indications for intervention. Patients with aneurysms should be treated with a covered stent or open surgical repair. Little new information has been published about FMD in the last 40 years. The recently instituted International Registry for Fibromuscular Dysplasia will remedy that situation and provide observational data on a large numbers of patients with FMD.     

Fibromuscular dysplasia of the brachial artery: a case report and review of the literature.

Fibromuscular dysplasia is a nonatherosclerotic, noninflammatory vascular disease that involves primarily medium-sized and small arteries. Fibromuscular dysplasia is characterized by medical fibrosis with or without smooth muscle cell hyperplasia and may produce luminal impingement with severe turbulence. Secondary aneurysmal deformity with or without thrombosis may also contribute to the obstruction. Fibromuscular dysplasia most commonly involves the renal and carotid arteries, with upper-extremity disease rarely reported. This case report describes a patient with digital embolization from brachial artery fibromuscular dysplasia. Angiography demonstrated significant narrowing and irregularity with a characteristic "string-of-beads" appearance of the right midbrachial artery. The abnormal segment was resected and reconstructed with a reversed saphenous vein graft. Histologic studies revealed disruption of the internal elastic lamina and disorientation of the hyperplastic medial smooth muscle cells characteristic of fibromuscular dysplasia.     

Bilateral brachial artery fibromuscular dysplasia

Fibromuscular dysplasia is a nonatherosclerotic, noninflammatory vascular disease that usually involves medium- and small-sized arteries. It is most commonly observed in the renal, carotid, and intracerebral arteries, although it has been reported in other arterial beds. The most common form is characterized by medial fibrosis, with or without smooth muscle cell hyperplasia, which can result in luminal narrowing and turbulent flow. There is often a secondary aneurysmal degeneration of the artery, which may or may not be associated with thrombosis or obstruction of flow. This accounts for the typical string-of-beads appearance seen on arteriography. We describe a patient who presented with ischemia of the right hand secondary to fibromuscular dysplasia of the brachial artery. Subsequent studies also demonstrated fibromuscular dysplasia in the other brachial artery as well as mild involvement of the right renal artery. The patient was treated on the symptomatic side with dilatation of proximal lesions, resection of the thrombosed segment, and reconstruction with a reversed saphenous vein graft. Distal pulses were fully restored postoperatively. Pathologic examination confirmed the arteriographic and clinical diagnosis of fibromuscular dysplasia. The salient features of this case are reviewed in addition to the other cases reported in the literature.     

Renal arteriovenous fistula associated with fibromuscular dysplasia

A case is reported of a woman with long-standing progressive hypertension and an abdominal bruit who on angiography demonstrated fibromuscular dysplasia of the right renal artery and an arteriovenous fistula in the upper pole of the right kidney. The various causes of renal arteriovenous fistula are reviewed. The relationship of mural aneurysms seen in fibromuscular dysplasia and the formation of arteriovenous fistulas by rupture of these aneurysms is discussed. Review of the English literature indicates a probable causal relationship between fibromuscular dysplasia of the renal arteries and intrarenal arteriovenous fistulas.     

A preliminary study of the role of duplex scanning in defining the adequacy of treatment of patients with renal artery fibromuscular dysplasia.

Renal artery fibromuscular dysplasia is a well-known cause of hypertension whose presence is confirmed by its typical arteriographic appearance. The functional significance of these lesions is often difficult to determine, particularly when both renal arteries are involved. Duplex scanning has been shown to be accurate for the detection of renal artery stenosis and estimation of the degree of narrowing. To test whether duplex scanning results after intervention correlate with clinical outcome, we reviewed the studies on nine patients with renal artery fibromuscular dysplasia who had been treated by either angioplasty or surgery. A total of 18 arteries were treated. Fourteen of the 18 treatments were successful as measured by a reduction in blood pressure and antihypertensive drugs. In four instances treatment was unsuccessful. For those patients who had clinical improvement, the hemodynamic parameters from the renal artery also improved. In the patients for whom treatment failed, the velocities recorded from the site of narrowing did not improve after intervention. Thus it appears that duplex scanning along with the clinical results may be used to document the basis for failing to improve after treatment be it angioplasty or operation.     

Asymptomatic renal infarction, due to fibromuscular dysplasia, in a young woman with 11 years of follow-up

We report a 27-year-old woman with renovascular hypertension, renal infarction, and hepatic artery aneurysm due to fibromuscular dysplasia. The patient was first noted to have renal artery aneurysm and hepatic artery aneurysm at the age of 17. The renal infarction was asymptomatic and was incidentally detected by magnetic resonance imaging (MRI) examination. Because of the rather peripheral location of the aneurysms, percutaneous transluminal renal artery angioplasty was considered inappropriate. This case suggests the need for long-term and periodical follow-up of patients with fibromuscular dysplasia.     

Fibromuscular Dysplasia of the Superior Mesenteric Artery-Case Report and Review of the Literature

Fibromuscular dysplasia is a multifactorial arteriopathy most commonly affecting the renal and carotid arteries. In this report we present a case of visceral artery involvement, causing occlusion of the superior mesenteric artery and celiac trunk and resulting in visceral ischemia. Treatment consisted of superior mesenteric artery reimplantation. Visceral artery FMD can present as occlusive or aneurysmal disease and treatment depends on patient characteristics and symptoms.     

Fibromuscular dysplasia of the superior mesenteric artery--case report and review of the literature

Fibromuscular dysplasia is a multifactorial arteriopathy most commonly affecting the renal and carotid arteries. In this report we present a case of visceral artery involvement, causing occlusion of the superior mesenteric artery and celiac trunk and resulting in visceral ischemia. Treatment consisted of superior mesenteric artery reimplantation. Visceral artery FMD can present as occlusive or aneurysmal disease and treatment depends on patient characteristics and symptoms.     

Symptomatic hydronephrosis from renal artery aneurysm associated with fibromuscular dysplasia: management with transarterial embolization

A 56-year-old woman presented with right-sided flank pain, dizziness, and nausea. Ultrasonography revealed hydronephrosis of the right kidney. CT showed a nodular mass at the ureteropelvic junction. Subsequent CT angiography revealed the nodular mass as a distal aneurysm of the right renal artery compromising the ureteropelvic junction. Selective diagnostic angiography confirmed the diagnosis of a distal renal artery aneurysm. Moreover, angiography incidentally detected fibromuscular dysplasia of both renal arteries. The renal artery aneurysm was then successfully managed by transarterial embolization using detachable bioactive coils.     

Repair of Bilateral Common Iliac Artery Aneurysms Coexisting with a Pelvic Horseshoe Kidney

This report describes the treatment of bilateral common iliac artery aneurysms in a patient with a pelvic horseshoe kidney. Anomalous renal arteries arising from the aorta, the common iliac arteries, and the left hypogastric artery were identified precisely by selective angiography. These multiple renal artery anomalies and the presence of a large pelvic horseshoe kidney complicated the surgical treatment of the aneurysms. The repair of the aneurysms was successfully accomplished by staged retroperitoneal procedures. This technique allowed excellent visualization of the iliac aneurysms and preservation of all renal arteries with intact renal function.     

Fibromuscular dysplasia of bilateral brachial arteries treated with surgery and consecutive thrombolytic therapy

A 61-year-old female was admitted to our hospital complaining of paresthesia, pain, and intermittent weakness in the right hand. A pulsating mass with bruits had developed on the patient's upper arm. We also noted an absence of radial artery pulsation. The angiographic findings revealed a classic "string of beads" appearance, which involved both brachial and renal arteries. The right brachial artery exhibited an aneurysm, which was filled with thrombus, and the distal radial artery was occluded with thromboemboli. We excised the abnormal brachial artery segment, replacing it with an autogenous reversed saphenous vein conduit. Consecutive thrombolytic therapy was then performed for the treatment of the radial artery embolism. Histological examination revealed that the patient was suffering from medial fibromuscular dysplasia. This uncommon form of fibromuscular dysplasia, which involves both brachial arteries with embolization, can be efficiently treated via surgery and consecutive thrombolytic therapy.